The Express finish has to be treated like Parkerizing (even though it ain't). You have to really soak it in oil until it soaks a bunch up. Use a small paint brush for this. My Express tried to rust when I first got it but it has stopped. Just keep a good coat of oil on it. I have been using Breakfree CLP for the last 10 years on it and it's staying rust free. The best thig to do with an Express though is have it Parkerized by a shop that does military rifle work. It will be the last finish you'll ever need on that gun.